Linkage isomerism,kinetics and electrochemistry of ruthenium-edta complexes of benzotriazole

The RuIII(edta)(benzotriazole)]− complex has been investigated in aqueous solution, by means of cyclic voltammetry, stopped-flow kinetics and spectroelectrochemistry. The formation reaction, starting from RuIII(edta)H2O]− and benzotriazole, leads essentially to the N(1) coordinated isomer. In the case of the RuII species, the products exhibit an intramolecular isomerization equilibrium involving the N(1) and N(2) binding sites, with K12=0.33. A complete set of acid/base and association constants has been obtained for the RuII and RuIII complexes. The data are coherent with theoretical calculations, reflecting the importance of π-backbonding interactions in the reduced species. This revised version was published online in June 2006 with corrections to the Cover Date.